Special Weather Statement, NWS Twin Cities, MN

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
657 AM CDT Thu Apr 17 2025

.KEY MESSAGES...

- Today, strong to severe thunderstorms possible this afternoon
  through this evening. Large hail is the primary threat.
  Localized heavy rain, damaging wind, or an isolated tornado
  can't be ruled out.

- Additional rain chances Sunday into early Monday, and again
  Tuesday of next week, but no significant weather impacts are
  expected.

&&

.DISCUSSION...
Issued at 244 PM CDT Wed Apr 16 2025

TODAY...Thunderstorms are expected to develop this afternoon and
last into the evening. A few storms could be strong to severe,
especially in southern Minnesota. The main threat is large hail,
but heavy rain, damaging winds, and an isolated tornado can't be
ruled out.

It was a dry and breezy morning, with dewpoints in the upper
20s to lower 30s,and winds out of the southeast at around 10 to
15 mph. That will change later today as a strong low level jet
will develop and advect moisture northward across the region.
Meanwhile southwest flow aloft has already brought an elevated
mixed layer across the region, with 500-700mb lapse rates around
7.5 to 8.5 C/km already in place across as shown via the SPC
Mesoanalysis page. The addition of low level moisture, together
with afternoon heating will lead to around 1000 to 2000 J/kg of
MLCAPE within in inverted surface pressure trough extending up
from Iowa into central Minnesota.

Storms are expected to develop this afternoon, and move
eastward this evening. Hodographs still show an elongated wind
profile, but there is veering in the lowest 3 km, and one could
argue that forecast soundings are more supportive of surface-
based storms than they were yesterday. For that reason, large
hail is still the primary threat, but damaging and an isolated
tornado can't be ruled out.

In addition to the severe threat, PWAT values will approach 1.1
to 1.3 inches, which is near record territory for mid-April.
Although the storms will be moving east, any storms that train
over the same area could dump 2 to 3 inches or more of rain over
an isolated area, which is supported by some of the individual
HiRes solutions. Since we have been fairly dry, the risk for
excessive runoff is low, so the flood risk would primarily be
for urban areas.

FRIDAY THROUGH WEDNESDAY...Lingering rain showers will last into
Friday before the system departs. Cooler and drier air will
follow into Saturday, with highs only in the low to mid 50s. On
Sunday, a shortwave trough over the Texas panhandle is forecast
to move up toward the Great Lakes. Widespread rain is expected
with this system. A westerly track would bring this rain across
Minnesota and Wisconsin, while an easterly track would only
bring rain to Wisconsin. Ensemble guidance off the ENS is
farther west, and the GEFS is farther east. The blended guidance
with highest rainfall chances east of I-35, and lesser amounts
to the west, seem appropriate. Forecast confidence in this
system should increase over the next couple of days.

Lastly, there is another shortwave expected to move through
Tuesday into Tuesday night. This will bring additional rain
chances, but it will be moving through quickly. There is a small
chance that we could build enough instability for storms, but at
this point it looks like rather low impact weather for next
week.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 655 AM CDT Thu Apr 17 2025

VFR early becoming MVFR/IFR this afternoon and evening.
VFR ceilings are expected to become SCT/BKN later this morning as a
cold front approaches from the SW. All sites can expect showers and
storms this afternoon and evening with an initial line of storms
developing across MN sites after 18-19z. There is a potential
for early shower development as early as 16z, however strongest
confidence remains during the afternoon hours. NW'ly sites can
expect SE winds to back to the E briefly before veering to the
NW this evening after the cold front passes. Lingering low level
cigs will keep categories limited to IFR/MVFR for the remainder
of the period.

KMSP...SE winds will continue to veer southerly through this morning
with gusts between 18-23kts. A cold front will approach KMSP from
the SW today which will begin to decrease ceilings after 16z. Hi-Res
guidance has hinted at a potential for a few showers to develop near
KMSP site however confidence in SHRA/TSRA coverage remains highest
between 21z and 01z this afternoon. Winds will quickly shift to the
NW after the cold front passes with cigs expected to remain high IFR
low MVFR for the remainder of the period with gusts near 20kts.

/OUTLOOK FOR KMSP/
FRI...MVFR/-SHRA early, then VFR. Wind NW 10-15G20kts.
SAT...VFR. Wind NW 10-15 kts.
SUN...Chc MVFR/-SHRA. Wind E 10-15 kts.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.

&&

DISCUSSION...JRB
AVIATION...Dunleavy

Hazardous Weather Outlook
National Weather Service Twin Cities/Chanhassen MN
359 AM CDT Thu Apr 17 2025

MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028-
180900-
Douglas-Todd-Morrison-Mille Lacs-Kanabec-Stevens-Pope-Stearns-
Benton-Sherburne-Isanti-Chisago-Lac Qui Parle-Swift-Chippewa-
Kandiyohi-Meeker-Wright-Hennepin-Anoka-Ramsey-Washington-
Yellow Medicine-Renville-McLeod-Sibley-Carver-Scott-Dakota-
Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth-
Waseca-Steele-Martin-Faribault-Freeborn-Polk-Barron-Rusk-
St. Croix-Pierce-Dunn-Pepin-Eau Claire-
359 AM CDT Thu Apr 17 2025

This Hazardous Weather Outlook is for portions of central and
southern Minnesota, and west central Wisconsin.

.DAY ONE...Today and Tonight.

Scattered thunderstorms expected later today, with a few severe
storms possible, mainly across southern Minnesota. Large hail
will be the primary severe hazard, but heavy rain, damaging wind,
and a brief tornado cannot be ruled out.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

SKYWARN spotter activation may be needed this afternoon through
this evening.

jrb

Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
Issued by National Weather Service Duluth MN
1149 AM CDT Thu Apr 17 2025

MNZ078-WIZ024>026-171715-
Goodhue MN-Pierce WI-Dunn WI-Pepin WI-
1149 AM CDT Thu Apr 17 2025

...Strong thunderstorms will impact portions of east central Goodhue,
Pepin, Pierce and southwestern Dunn Counties through 1215 PM CDT
...

At 1148 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Ellsworth to Frontenac. Movement was east
at 60 mph.

HAZARD...Half inch hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to outdoor objects is possible.

Strong thunderstorms will be near...
  Ellsworth and Plum City around 1155 AM CDT.
  Eau Galle, Elmwood, and Durand around 1205 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4459 9202 4441 9209 4444 9221 4445 9224
      4446 9240 4478 9278 4483 9257 4486 9230
      4486 9214 4488 9214 4489 9205 4460 9165
TIME...MOT...LOC 1648Z 248DEG 53KT 4469 9256 4451 9232

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...<30 MPH

Moore